The present disclosure generally relates to a bucket for a work machine and, more particularly, to a modular bucket assembly having fatigue life optimized weld seams.
A bucket is a tool attachment commonly fitted to wheel loaders, excavators, backhoes, skid steers, and other work machines. Depending on the work machine's application, which may relate to construction, mining, agriculture, earth moving, trenching, etc., the bucket may be used to penetrate into a material, such as dirt or gravel, transport a material, dump a material, clear a worksite, and/or level a terrain, among other possible use cases. Accordingly, a bucket for a work machine may be designed to satisfy varying capacity requirements, strength requirements, functionality, and customer preferences. Given their variety, buckets are often manufactured after a customer order is placed in order to meet the customer's specific applicational needs. Unfortunately, the required processing time to manufacture a custom bucket without prebuilt components may often be unsatisfactory. For example, a turnaround time for larger sized buckets may exceed 16 weeks while many customers may expect turnaround in 6 weeks or less.
One method of reducing manufacturing time may involve separating a bucket into components, one or more of which may be generic and prebuilt. It is generally known in the art to manufacture a bucket assembly by welding together separate components. It is further known that certain features of a bucket assembly, which may include guard modules, edge modules, and side plates, may be altered in size and capacity to control or match the size and capacity of the complete assembly. However, there is a need for a modular bucket assembly and method of manufacturing thereof whereby a universal and prebuilt bucket core is welded with an elective extension module. Moreover, there is a need to resolve the reduction in fatigue life attributed to welding together separate components of a bucket assembly. For the purposes of this disclosure, fatigue life may be defined as the number of loading cycles an object or material sustains before experiencing failure of a specified nature, such as a fracture. Fatigue life may be calculated through a number of methods commonly employed in the art, including but not limited to the stress-life method, the strain-life method, and the linear-elastic fracture mechanics method; and the calculation may consider a number of factors commonly known in the art, such as but not limited to the type of loading, the magnitude of the stress or strain cycle, and the nature of the failure.
One example of relevant prior art is found in U.S. Pat. No. 8,839,534 invented by Zeno et al. and assigned to ACS Industries, Inc. (hereinafter “Zeno”), which discloses a monolithic floor for use with a hot slag bucket. In Zeno, a monolithic (i.e. continuous and homogenous) floor having varied size, thickness, and/or capacity may be welded to a bucket and provide a working edge to the bucket. However, Zeno teaches that a new bucket may be modified in order to properly integrate with monolithic floors of differing type and dimension; and/or that an existing bucket may be retrofitted and cut in order to accept the monolithic floor. Zeno thus fails to teach a modular bucket assembly comprising a universal bucket core. Furthermore, the bucket design taught by Zeno is primarily concerned with reducing warpage caused by heating and cooling from hot slag. Zeno does not address the stress concentrations arising from weld seams connecting the monolithic floor to the bucket.
Accordingly, there remains a need for a bucket assembly and method of manufacturing that modularizes a bucket assembly, enables production of both universal and customizable buckets and bucket components, and alleviates fatigue life reduction created by weld seams.
According to a first aspect of the present disclosure, a bucket core for a work machine is disclosed. The bucket core comprises a pair of side sections, the side sections being spaced apart to define a width of the bucket. The bucket core comprises a continuous wrapper extending between the pair of side sections, including a substantially planar, upward sloping, upper section; an arcuate middle section; a substantially planar, downward sloping, first lower section; an obtuse bend; and a substantially planar, second lower section. The bucket core comprises a supporting element extending between the pair of side sections, the supporting element being attached to a rear of the upper section. The bucket core comprises a bracing element removably attached to the wrapper. The pair of side sections and the wrapper define a receptacle of the bucket core. Notably, one or more stress concentrations during an operation of the bucket core occur(s) on the obtuse bend.
According to a second aspect of the present disclosure, a bucket assembly for a work machine is disclosed. The bucket assembly comprises a bucket core including a pair of side sections, the side sections being spaced apart to define a width of the bucket. The bucket core comprises a continuous wrapper extending between the pair of side sections, including: a substantially planar, upward sloping, upper section; an arcuate middle section; a substantially planar, downward sloping, first lower section; an obtuse bend; and a substantially planar, second lower section. The bucket core comprises a supporting element extending between the pair of side sections, the supporting element being attached to a rear of the upper section. The pair of side sections and the wrapper define a receptacle of the bucket core. The bucket assembly further comprises an extension module attached to the bucket core. The extension module includes a pair of side bars operatively and respectively attached to the pair of side sections, the pair of side bar being spaced apart to equal the width of the bucket; a guard module extending between the pair of side sections and attached to the upper section of the wrapper; and an edge module extending between the pair of side sections and operatively attached to the second lower section of the wrapper.
According to a third aspect of the present disclosure, a method of manufacturing a bucket assembly for a work machine is disclosed. The method comprises prebuilding a bucket core; receiving an order for said bucket assembly, the order reflecting at least one custom requirement; providing a plurality of parts for manufacturing an extension module based on the at least one custom requirement; and attaching the bucket core and at least some of the plurality of parts for the extension module. The extension module includes at least one of a guard module, a pair of side bars, and an edge module.
According to a fourth aspect of the present disclosure, the step of prebuilding the bucket core further includes providing a continuous wrapper having a substantially planar, upward sloping, upper section; an actuate middle section; a substantially planar, downward sloping, first lower section; an obtuse bend, and a substantially planar, second lower section.
According to a fifth aspect of the present disclosure, the step of prebuilding the bucket core further includes attaching a supporting element to a rear of the upper section of the wrapper.
According to a sixth aspect of the present disclosure, the step of prebuilding the bucket core further includes attaching a pair of side sections to the supporting element and the wrapper, wherein the side sections are spaced apart to define a width of the bucket assembly.
According to a seventh aspect of the present disclosure, the step of prebuilding the bucket core further includes attaching a hinge plate assembly to the wrapper, wherein the hinge plate assembly is laterally positioned between the side sections and includes a pair of inner hinge plates and at least one pair of outer hinge plates.
According to an eighth aspect of the present disclosure, the step of attaching the bucket core to at least some of the plurality of parts for the extension module further includes attaching the guard module to a pair of side sections of the bucket core.
According to a ninth aspect of the present disclosure, the step of attaching the bucket core to at least some of the plurality of parts for the extension module further includes attaching the edge module to a pair of side sections of the bucket core.
According to a tenth aspect of the present disclosure, the step of attaching the bucket core to at least some of the plurality of parts for the extension module further includes attaching the pair of side bars to the guard module and the edge module.
According to an eleventh aspect of the present disclosure, the step of attaching the bucket core to at least some of the plurality of parts for the extension module further includes attaching the pair of side extension plates to the guard module and the first edge extension plate.
According to a twelfth aspect of the present disclosure, the step of prebuilding the bucket core further includes removably attaching a bracing element to the wrapper.
According to a thirteenth aspect of the present disclosure, the bracing element is removably attached to the upper section via a bolt and removably attached to the second lower section via a clamp.
According to a fourteenth aspect of the present disclosure, the step of attaching the bucket core to at least some of the plurality of parts for the extension module further includes removing the bracing element from the wrapper before attaching the bucket core to at least some of the plurality of parts for the extension module.
These and other aspects and features of the present disclosure will be more readily understood after reading the following description in conjunction with the accompanying drawings.
Referring now to the drawings and with specific reference to
The work machine 3 may further include an implement arm 35 attached to the frame 31 at a proximal end and attached to a bucket assembly 1 at a distal end. While the implement arm 35 is depicted as a boom in the exemplary embodiment, it may instead comprise a stick, a lift arm, one or more actuating cylinders, one or more linkages, and/or a combination thereof, depending on the specific work machine 3. The work machine 3 may be employed in a number of operations which utilize the bucket assembly 1, for example in construction, agricultural, mining, or earth moving contexts, in order to dig, scoop, lift, transport, lower, dump, grade, and/or level a variety of materials.
Turning now to
The bucket assembly 1 may comprise a variety of dimensions, volume and weight capacities, strength grades, functionality, and/or other features depending on specific applicational requirements. Consequently, to improve a modularity and decrease a manufacturing time of the bucket assembly 1, the bucket assembly 1 may be separated into a bucket core 100 and an extension module 200. The bucket core 100 may be a “universal” component, i.e. it may be common across some or all bucket assemblies 1. The extension module 200 may be a “customizable” component, i.e. it may be unique to one or some bucket assemblies 1. Accordingly, in different embodiments the extension module 200 may be configured with varying designs, dimensions, and materials depending on specific applicational requirements. Generally speaking, the bucket core 100 may be manufactured and stocked prior to an order, such as a customer order, whilst the extension module 200 may be manufactured after. In some embodiments, however, the extension module 200 and/or its parts may be manufactured to predate the customer order as well.
Turning now to
The anatomy of the wrapper 120 may be best visualized in
Returning now to
In some embodiments, the bucket core 100 may further comprise a hinge plate assembly 140 laterally positioned between the pair of side sections 110 and attached to the wrapper 120 and/or the supporting element 130. The hinge plate assembly 140 may include a pair of inner hinge plates 141, each inner hinge plate 141 including a bore 1411; and at least one pair of outer hinge plates 142, each outer hinge plate 142 including a bore 1421. The pair of inner hinge plates 141 and their bores 1411 may be axially aligned and configured to receive and support a stick pin (not shown) in connection with the implement arm 35 of the work machine 3. Similarly, the at least one pair of outer hinge plates 142 and their bores 1421 may be axially aligned and configured to receive and support an actuator pin (not shown) in connection with the implement arm 35 of the work machine 3.
In various embodiments, and by way of non-limiting example, the pair of side sections 110, wrapper 120, supporting element 130, and hinge plate assembly 140 may be formed of steel, chromium carbide, or another desired material. One or more such components may be made of different material(s) than other such components, as well as combinations of different materials. To assemble the bucket core 100, each of the components may be welded or otherwise connected together as known in the art. In some embodiments, the bucket core 100, including the pair of side sections 110, the wrapper 120, and the supporting element 130, may be fully welded before the core 100 is attached to the extension module 200 or to at least some of a plurality of parts of the extension module 200.
Turning now to
As previously discussed, the bucket core 100 may constitute a universal component of the bucket assembly 1 and may be generic across a number of bucket assembly 1 designs and use cases. To customize the final bucket assembly 1, the bucket core 100 may be fitted with an extension module 200 which dictates the depth, volume/weight capacity, strength, functionality, and/or other customizable features of the bucket assembly 1. As best seen in
In various embodiments, the edge module 230 may feature different topologies, e.g. may be planar or sloping; may feature different profiles, e.g. may be rectangular, triangular, or arcuate in shape; may include teeth or a flat cutting edge; and may include yet other features depending on specific applicational requirements. In some embodiments, the edge module 230 represents the component of the extension module 200 with the greatest flexibility in design and the greatest influence to the customization of the bucket assembly 1 as a whole. It may be understood that, after attachment, the edge module 230 may partly define an opening of the bucket assembly 1 and may partly dictate its depth, volume/weight capacity, strength, functionality, and/or other customizable features.
Referring now to
In various embodiments, the components of the extension module 200, including the pair of side bars 210, the guard module 220, the edge module 230, and/or the extension plates 240, 250, 260 may be formed of steel, chromium carbide, or another desired material. One or more such components may be made of different material(s) than other such components, as well as combinations of different materials. To complete the bucket assembly 1, each of the components may be fully welded to the bucket core 100.
After attachment, the edge module 230 may be substantially parallel to the second lower section 125 and paddle plate 126 of the wrapper 120, and may be parallel to the ground when the bucket assembly 1 is in a neutral position. It may be appreciated by those in the art that stresses exerted on the edge module 230 during an operation of the bucket assembly 1 may be transferred through the edge module 230, the edge extension plates 250, 260, the weld seams 303-306, the wrapper 120, and yet other components of the bucket assembly 1. Advantageously, the designs disclosed herein may shift one or more stress concentrations exhibited during an operation of the bucket assembly 1 away from the plurality of weld seams 303-306 and into the interior of the bucket core 100. In particular, the one or more stress concentrations may be localized to the bend 124 of the wrapper 120. By incorporating the inflection point, i.e. the bend 124, within the bucket core 100, and, more specifically, on the continuous wrapper 120, a stress concentration may be thus be transferred to a more durable feature of the bucket assembly 1 and a fatigue life generally improved.
Turning now to
The bucket assembly of the present disclosure may be employed in any number of work machines, including but not limited to wheel loaders, skid steers, excavators, backhoes, mining shovels, and others. In an exemplary application, the bucket assembly may be attached to an implement arm of a wheel loader, such as a Caterpillar® 988K Large Wheel Loader or a Caterpillar ® 992 Large Wheel Loader. The bucket assembly may further be employed in any number of operations common to the art, including but not limited to digging, trenching, excavating, transporting, dumping, grading, leveling, and others, which may be performed in the context of agricultural, construction, mining, road building, trenching, and other work machine applications.
By employing the disclosed designs, a modular bucket assembly may be substantially customizable while avoiding increases in fabrication lead time and decreases in fatigue life. Advantageously, the bucket assembly may be separated into a universal bucket core and a customizable extension module, wherein the universal bucket core may be prebuilt and readily stocked. Accordingly, at least half and possibly upwards of three quarters of the total processing time may be completed prior to a customer order. The extension module may be custom built and may be designed to fulfill a depth, volume/weight capacity, strength, functionality, and/or other feature of the bucket assembly. Accordingly, less than half or possibly as little as a quarter of the total processing time may be required after the customer order, such that the complete bucket assembly may be manufactured, joined, and shipped in six weeks or less time. In some embodiments, certain components of the extension module, such as the guard module, the pair of side bars, or the extension plates may be prebuilt and stocked as well, achieving yet further reductions to total processing time. And in other embodiments, components of the bucket assembly may be manufactured according to business forecasts and predate the customer order altogether.
Moreover, the disclosed bucket assembly may be modularized to the above benefits without detriment or with limited detriment to fatigue life. By designing a bucket assembly with an inflection point localized to the bucket core, and specifically a bend of a continuous wrapper of the bucket core, stress concentrations during an operation of the bucket assembly may be relocated from the weld seams—areas traditionally known to concentrate stress and exacerbate fatigue. Accordingly, a fatigue life of the bucket assembly may be improved in tandem with customization.
Turning now to
Referring now to
In some embodiments, the aforementioned components of the bucket core may be attached by full welding, and may be assembled before the bucket core is attached to at least some of the parts of the extension module. In the same or other embodiments, a bracing element may be removably attached to the bucket core upon its completion to provide temporary structural support (block 1315). In various embodiments, an upper frame of the bracing element may be attached to the upper section of the wrapper via a bolt and a lower frame of the bracing element may be attached to at least one of the first lower section, the obtuse bend, and the second lower section via clamping; the upper frame and the lower frame may be tack-welded to the continuous wrapper; or the bracing element may be removably attached to the bucket core 100 according to other methods common to the art.
Turning now to
In block 1342, the guard module may be attached to a distal end of an upper section of the continuous wrapper. In some embodiments, the guard module may further be attached to the side sections of the bucket core. The edge module may be operatively attached to at least one of a distal end of a second lower section and to a distal end of a paddle plate of the wrapper. In some embodiments, the edge module may be directly attached to the wrapper (block 1344) or, in other embodiments, a first extension plate may be attached to and between the distal end of the second lower section and the edge module, while a second extension plate may be attached to and between the distal end of the paddle plate and the edge module (block 1343). In some embodiments, the edge module may further be attached to the side sections of the bucket core.
A pair of side bars may further be operatively and respectively attached to a pair of side sections of the bucket core and, more specifically, to a front profile of the side sections. In some embodiments, the side bars may be directly and respectively attached to the front profile of the pair of side sections (block 1346) or, in other embodiments, a pair of side extension plates may be attached to and between the pair of side sections and the pair of side bars (block 1345). In some embodiments, the side bars may further be attached to the guard module and the edge module. And in other embodiments, where applicable, the side extensions may be attached to the guard module and the first edge extension plate.
According to many embodiments, each of the above attachment steps may be effected by welding together the adjoining components, such that at least some of the plurality of parts for the extension module are fully welded to the bucket core upon completion of the bucket assembly 1.
While the preceding text sets forth a detailed description of numerous different embodiments, it should be understood that the legal scope of protection is defined by the words of the claims set forth at the end of this patent. The detailed description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims defining the scope of protection.